The present invention relates to a process for the production of 3-mono or 3,5-disubstituted-4-acetoxystyrene wherein the 3- or 3,5-substitution is independently C.sub.1 to C.sub.10 alkyl, chlorine, bromine, iodine, --NO.sub.2, --NH.sub.2, or --SO.sub.3 H; a process for its polymerization, and hydrolysis. In its most preferred form, the invention relates to 3-mono- and 3,5-dihalogenated-4-acetoxystyrenes which contain chlorine or bromine as the halogen, and a method of preparation thereof. 3,5-dibromo-4-hydroxystyrene compounds have been known for a long time and were initially prepared from 4-hydroxycinnamic acid by
(a) bromination of positions 3 and 5 on the ring as well as addition of bromine to the double bond, PA1 (b) dehydrobromination with concurrent decarboxylation, leading to reconstitution of the vinylic double bond, PA1 (c) then, addition of hydrogen bromide to said double bond to form a saturated vicinal dibromide, PA1 (d) finally, by debromination for reconstitution of the vinylic double bond (see Liebigs Annalen der Chemie, 322, 235 (1902)) as shown in the following scheme: ##STR1## PA1 (a) acylating phenol to produce 4-hydroxyacetophenone; and PA1 (b) reacting the 4-hydroxyacetophenone with a reagent under conditions to form 3-mono or 3,5-disubstituted-4hydroxyacetophenone; and PA1 (c) esterifying the 3-mono or 3,5-disubstituted-4hydroxyacetophenone, preferably with acetic anhydride, to form 3-mono or 3,5-disubstituted-4-acetoxyacetophenone; and PA1 (d) reducing the 3-mono or 3,5-disubstituted-4-acetoxyacetophenone with a sufficient amount of a reducing agent to produce 1-(3'-mono or 3', 5'-disubstituted-4'-acetoxyphenyl)ethanol; and PA1 (e) dehydrating the 1-(3'-mono or 3,5'-disubstituted-4,-acetoxyphenyl)ethanol to produce 3-mono or 3,5-disubstituted-acetoxystyrene; PA1 (a) acylating phenol, preferably with acetic anhydride and using HF as a catalyst to produce 4-hydroxyacetophenone; and PA1 (b) reacting the 4-hydroxyacetophenone with a reagent under conditions to form 3-mono or 3,5-disubstituted-4hydroxyacetophenone; and PA1 (c) esterifying the 3-mono or 3,5-disubstituted-4hydroxyacetophenone, preferably with acetic anhydride to form 3-mono or 3,5- disubstituted-4-acetoxyacetophenone; and PA1 (d) reducing the 3-mono or 3,5-disubstituted-4acetoxyacetophenone with a sufficient amount of a reducing agent to produce 1-(3'-mono or 3',5',-disubstituted-4'-acetoxyphenyl)ethanol; and PA1 (e) dehydrating the 1-(3'-mono or 3',5',-disubstituted-4-acetoxyphenyl)ethanol to produce 3-mono or 3,5-disubstitutedacetoxystyrene; and PA1 (f) free radical polymerization of the 3-mono or 3,5-disubstituted-4-acetoxystyrene to form poly(3-mono or 3,5-disubstituted-4-acetoxystyrene) having a molecular weight in the range of from about 1,000 to about 800,000, preferably about 5,000 to about 500,000; PA1 (a) acylating phenol, preferably with acetic anhydride to produce 4-hydroxyacetophenone; and PA1 (b) reacting the 4-hydroxyacetophenone with a reagent under conditions to form 3-mono or 3,5-disubstituted-4-hydroxyacetophenone; and PA1 (c) esterifying the 3-mono or 3,5-disubstituted-4-hydroxyacetophenone, preferably with acetic anhydride to form 3-mono or 3,5- disubstituted-4-acetoxyacetophenone; and PA1 (d) reducing the 3-mono or 3,5-disubstituted-4-acetoxyacetophenone with a sufficient amount of a reducing agent to produce 1-(3'-mono or 3',5'-disubstituted-4-acetoxyphenyl)ethanol; and PA1 (e) dehydrating the 1-(3'-mono or 3',5'-disubstituted-4-acetoxyphenyl)ethanol to produce 3-mono or 3,5-disubstituted-4-acetoxystyrene; and PA1 (f) free radical polymerization of the 3-mono or 3,5-disubstituted-4-acetoxystyrene to form poly(3-mono or 3,5-disubstituted-4-acetoxystyrene) having a molecular weight in the range of from about 1,000 to about 800,000, preferably about 5,000 to about 500,000; and PA1 (g) hydrolyzing the poly(3-mono or 3,5-disubstituted-4-acetoxystyrene) to form poly(3-mono or 3,5-disubstituted-4-hydroxystyrene) having a molecular weight in the range of from about 1,000 to about 500,000, preferably about 5,000 to about 500,000; PA1 (a) halogenation of a 4-hydroxyacetophenone with general formula ##STR2## wherein R1 is hydrogen or alkyl, in particular C.sub.1 -C.sub.10 alkyl,and PA1 R2 and R3 are independently hydrogen, alkyl, alkoxy, or halogen, PA1 wherein R1 and R2 may also be combined to form a cycloaliphatic ring, consisting in particular of 6 to 12 members; and PA1 (b) esterification (protection) of the hydroxyl function to form a halogenated 4-acetoxyacetophenone derivative; and PA1 (c) reduction of the ketone function to a hydroxyl function, (d) dehydration to form 3-mono or 3,5-dihalogenated 4-acetoxystyrene, and where appropriate PA1 (e) hydrolysis of the protective group to form the 3-mono or 3,5-dihalogenated 4-hydroxystyrene. PA1 R1 is hydrogen or (C1--C3) alkyl, especially methyl; and PA1 R2 and R3 are preferably the same and are hydrogen, (C1-C3) alkyl, (C1-C3) alkoxy, or bromine.
The existing process, based on cinammic acid derivatives, does however have considerable disadvantages in terms of the preparation method. In particular, the decarboxylation necessary in this method proves to be disadvantageous. Moreover, out of 7 bromine atoms required in the course of this synthesis, only 2 remain in the final product. It was therefore desirable to develop a synthesis making more economical use of bromine.
It is known in the art to produce monomers, homopolymers and copolymers of unsubstituted 4-acetoxystyrene and to hydrolyze the same to produce 4-hydroxystyrene derivatives or polyvinyl phenols. Such find use in the production of photoresists, adhesives, coating compositions, and the like. In particular, polymers or copolymers prepared from non-halogenated monomers are used for preparing coating compositions and as binders for photoresists. In this connection, reference is made to postbrominated poly(4-hydroxy)styrenes which are used in accordance with German patent application No. P 37 30 784.3 as radiation-sensitive compounds in corresponding photoresists. The monomeric acetoxystyrene of this invention finds use as an intermediate in the production of such polymers as poly(3-mono or 3,5 dimethyl-4-acetoxystyrene) and poly(3-mono or 3,5-dimethyl-4hydroxystyrene). These later compounds are useful as improved binder resins for photoresists which have a more advantageous dissolution rate in commercially accepted photoresist developers, and are more fully described in U.S. patent application Ser. No. 097,815 filed on Sept. 16, 1987 and which is incorporated herein by reference. Alpha acetoxystyrene and beta acetoxystyrenes are described in U.S. Pat. No. 4,144,063 and acetoxymethylstyrene is taught in U.S. Pat. No. 3,963,495. U.S. Pat. No. 4,075,237 describes 1,4-dimethyl-2hydroxystyrene, while U.S. Pat. No. 4,565,846 teaches the use of poly(3,5-dimethyl-4-hydroxystyrene). Japanese patent 84023747 describes anti-static compounds employing poly-acetoxymethylstyrene and U.S. Pat. No. 4,221,700 describes a stabilized synthetic polymer composition using poly(alkylated alkenylphenol) including 2methyl paravinyl phenol. U.S. Pat. No. 4,600,683 and 4,543,397 describe poly (alphamethyl vinylphenol). U.S. Pat. Nos. 4,517,028; 4,460,770 and 4,539,051 describe dimethyl vinyl phenol.
One preferred product of this invention is 3,5-dibromo-4-hydroxystyrene which is particularly useful as a binding resin for o-quinone diazides in the production of x-ray sensitive photoresists.